This invention has been created without the sponsorship or funding of any federally sponsored research or development program.
The present invention is generally directed to an apparatus for and a method of developing fingerprints and specifically with the use of cyanoacrylate (super glue).
The two methods which are currently in use for developing fingerprints with cyanoacrylate fuming either use heat and humidity or vacuum to accelerate the evaporization of the cyanoacrylate.
The use of heat or humidity with cyanoacrylate for developing fingerprints is the most common method currently in use. The process is simple, quick, inexpensive and produces durable latent prints on a variety of surfaces. However, there is a danger of overfuming if the articles of evidence bearing the fingerprints are not continually monitored during the fuming process. Also, the articles do not always fume evenly, especially articles with irregular surfaces, which includes most articles of evidence.
The vacuum method of cyanoacrylate fuming virtually eliminates the danger of overfuming and causes items to fume more evenly. Even items with very irregular surfaces, such as firearms or crumpled plastic bags, fume evenly. However, the fuming process requires more time (sometimes several hours), and it is difficult to monitor the process as the articles are usually out of view while in the vacuum. Results can be inconsistent and quite often items have to be re-fumed after the initial fuming and examination due to lack of development. The vacuum process also develops prints that are often less visible, and usually fluorescent dyes and a forensic light are needed to view prints. These and other difficulties experienced with the prior art coating systems have been obviated by the present invention.
It is, therefore, a principal object of the invention to provide a method of developing fingerprints which retains the advantages of the vacuum method of cyanoacrylate fuming and the heat method of cyanoacrylate fuming without the disadvantages of either prior method.
A further object of the invention is the provision of an apparatus for cyanoacrylate fuming which utilizes heat and vacuum.
Another object of the present invention is to provide an apparatus for cyanoacrylate fuming which produces clear fingerprints in a short amount of time and is easy to use.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.
In general, the invention consists of an apparatus for and method of developing fingerprints on an object by cyanoacrylate fuming. The apparatus includes a container having a chamber, an opening to the chamber and a mechanism for evacuating air from the chamber. The apparatus also includes a cover for hermetically sealing the opening, an exposed upper surface in the chamber for receiving drops of cyanoacrylate and an electrical heater for heating the exposed upper surface. More specifically, the electrical heater is located in the chamber and supports a receptacle which has the exposed upper surface. The electrical heater has an electrical cord that extends through a fixture which is attached to the cover. The cover, fixture and electrical cord are all sealed relative to the container to enable air to be evacuated from the chamber. The method of the present invention includes heating the receptacle, placing the object to be examined into the chamber, placing the receptacle in the chamber, placing a few drops of cyanoacrylate on the upper surface of the receptacle, applying the cover to the opening of the container, and pumping air from the chamber. The pump is then turned off. After the fuming of the cyanoacrylate, the cover is removed to remove the object from the chamber.